The DE 101 36 255 B4 discloses the device for production of fibres from solution or melt of polymer with spinning electrode formed of a system of parallel wires positioned on a pair of endless stripes belted around two guiding cylinders, which are positioned one above another, while the lower guiding cylinder extends into the solution or melt of polymer. The spinning electrode is connected to the high voltage source together with the counter-electrode, which is formed of electrically conductive rotating stripe. Solution or melt of polymer are carried out by means of wires into electric field between the spinning electrode and the counter-electrode, where from the solution or melt of polymer the fibres are created, which are carried towards the counter-electrode and they fall to the web positioned on the counter-electrode. The disadvantage is a long time of staying of solution or melt of polymer in electric field, because the solution as well as the melt of polymer grows old quite quickly and during the spinning process it changes its properties which causes changes in parameters of created fibres, especially their diameter. Another disadvantage is positioning of wires of the spinning electrode on a pair of endless stripes, which must be electrically conductive and they affect very negatively an electric field being created between the spinning electrode and counter-electrode.
Further from the U.S. Pat. No. 4,144,553 there is known the device for electrodynamic applying of solutions, dispersions and mixtures of solid substances on substratum material by means of a suitable electric field. The device contains two reservoirs with applied substrate, in which there are positioned pulleys belted with endless stripe, by means of which the substrate is delivered into electric field, in which it is applied on the substratum material, which is passing next to one or both lateral sides of endless stripe. This device is not able to produce fibres, but it is designated only for applying of solutions, dispersions, etc.
Further there are known the devices for production of nanofibres through electrostatic spinning of polymer solution, which contain the rotation spinning electrodes of an oblong shape, e.g. according to the WO 2005/024101 A1. This device contains the spinning electrode in the shape of cylinder, which according to its main axis rotates and by its lower part of surface is dipped into polymer solution. The polymer solution by surface of the cylinder is carried out into electric field between the spinning and collecting electrode, where the nanofibres are formed, which are carried towards the collecting electrode and before it they deposit on the substratum material. This device is able to produce very good nanofibres from water polymer solutions, nevertheless the solutions of polymers soluble in nonaqueous solvents can be processed by means of this device quite difficult. Further, the layer of nanofibres applied on the substratum material is not even.
Evenness of the created layer of nanofibres may be achieved by means of the device according to the CZ PV 2005-360, which describes the spinning electrode comprising a system of lamellas arranged radial and longitudinally towards the rotation axis of the spinning electrode, while the wrapping surface of a part of surface of the spinning electrode serving for carrying out of the polymer solution into electric field have the wrapping surface, which in the plane passing through axis of the spinning electrode and perpendicular to the plane of substratum material has a shape formed of equipotential line of the highest intensity of electric field between the spinning electrode and collecting electrode. Such spinning electrode is able to carry out a sufficient quantity of polymer solution into the most suitable places of electric field between the spinning and collecting electrode and at the same time to spin quite good also the nonaqueous polymer solutions and to create an even layer of nanofibres. Nevertheless the disadvantage is the demanding production of such spinning electrode, and due to this its price.
As to the production, less costly seems to be the spinning electrode according to the CZ PV 2006-545, which comprises a pair of faces, between which there are mounted by wire formed spinning members distributed evenly around the perimeter of the faces, while the faces are produced of electrically non-conductive material and all spinning members are mutually electrically connected in a conductive manner. Rotating spinning electrode created in this way is able to spin the water as well as nonaqueous polymer solutions and along its whole length it achieves quite high spinning effect as to its evenness, while electric field for spinning is formed between individual spinning members after their getting out from polymer solution and gradual approaching towards the collecting electrode.
Disadvantage of all rotating spinning electrodes of an oblong shape as well as the device for production of nanofibres through electrostatic spinning of polymer solutions, that contain the rotating spinning electrodes of oblong shape is especially high quantity of polymer solution in reservoir of polymer solution into which the spinning electrodes extend by a section of their surface. The reservoirs have a large opened surface on which not only massive evaporating of solvent from polymer solution occurs but also e.g. at the solutions with hygroscopic solvents, the polymer solution thickens and grows old very fast and it must be added and replaced continuously. This increases the costs for production of nanofibres and at the same time reduces quality of produced nanofibres. The polymer solution into electrostatic field for spinning is delivered by surface of cylindric rotating spinning electrode relatively slowly, and so it gradually gets dry on the surface and at the next dipping of the respective place of surface of the rotation spinning electrode there gets stuck a greater quantity of polymer solution, which gradually causes degradation of the spinning process and surface of the spinning electrode must be cleaned. To clean the spinning electrode, the spinning process must be interrupted. At the cord rotation spinning electrode the polymer solution into electrostatic field is delivered on individual cords, which represent active spinning zones and which during spinning change their position in electrostatic field. This brings further disadvantage, as during spinning on the active spinning zone of the spinning electrode the intensity is of electrostatic field is changed, which results in production of nanofibres of various diameters and reduces qualitative evenness of produced nanofibres.
The goal of the invention is to propose a method and create device for production of nanofibres through electrostatic spinning of polymer solutions possibly of liquid matrixes containing especially polymer solutions in electrostatic field, which at the industrial utilisation would be able from the long-term period to produce nanofibres of a constant quality with the lowest possible demand for maintenance and adjustment and to design the spinning electrode, which would remedy or at least reduce disadvantages of the background art.